P0063 means the heater control circuit for the Bank 2, Sensor 3 oxygen sensor is seeing a low voltage condition, indicating the sensor's heater is not getting enough power to reach its operating temperature. This can prevent the sensor from providing accurate feedback to the engine control module.
The heater resistor inside the oxygen sensor has opened or shorted, preventing it from heating properly.
Chafed, broken, or corroded wires, or a loose/pinned connector can cause low voltage or an open circuit.
The fuse or relay supplying power to the sensor heater may have failed, cutting off voltage.
Corrosion or looseness at the sensor ground point can prevent the heater from completing its circuit.
The oxygen sensor heater driver inside the powertrain control module may be defective, though this is uncommon compared to sensor or wiring issues.
No. The PCM is rarely the cause; most P0063 cases stem from a faulty sensor heater, wiring/connector issues, or a blown fuse. Replacing the PCM should only be considered after those components have been tested and found good.
You can usually drive short distances, but the engine may run less efficiently and emissions could be elevated. Prolonged operation with a malfunctioning oxygen sensor heater can lead to increased fuel consumption and potential catalyst damage.
Only the sensor indicated by the code (Bank 2, Sensor 3) needs to be tested and possibly replaced. Other sensors should be evaluated only if they show their own faults.